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Hidetomo Nakamoto

Publications and source records attributed to Hidetomo Nakamoto.

At least 19 recordsLinked to original sources
PubMed2006

Hypoalbuminemia is an important risk factor of hypotension during hemodialysis.

Hypotension during hemodialysis (HD) is an important problem in patients on HD. To investigate the risk factors that contribute to the hypotension during HD, we compared background factors of hypotensive (HP) patients during HD. Among 58 patients undergoing HD in Tamura Memorial Hospital, 12 patients could not continue full HD because of hypotension. We compared the data of ultrafiltration volume, cardiothoracic ratio (CTR), total protein (TP), serum albumin, blood urea nitrogen (BUN), serum creatinine, total cholesterol (TC), hemoglobin (Hb), blood glucose (BS), brain natriuretic peptide (BNP), and cardiac function between HP patients (HP group; n=12) and sex- and age-matched control patients (NP group; n=12). There were no significant differences of age, sex, and duration of HD between the 2 groups. Cardiothoracic ratio is bigger and BNP is higher in the HP group compared with the NP group (CTR: HP 55.8+/-2.9% vs. NP 47.7+/-1.1%, p=0.0165; BNP: HP 602+/-171 vs. NP 147+/-38, p=0.0167). Serum albumin in the HP group is significantly lower compared with the NP group (HP 3.2+/-0.1 g/dL vs. NP 3.5+/-0.1 g/dL, p=0.0130). However, there were no significant differences of ultrafiltration rate (UFR), BS, TC, Hb, and cardiac function between the 2 groups. There is a significant negative correlation between changes of systolic blood pressure (delta systolic blood pressure) and serum albumin in these patients (r=-0.598, p=0.0016). From these data, we conclude that hypoalbuminemia is a major risk factor of hypotension during HD.

Aged↗
PubMed2006

Early estimation of high peritoneal permeability can predict poor prognosis for technique survival in patients on peritoneal dialysis.

At the beginning of continuous ambulatory peritoneal dialysis (CAPD), different patients exhibit large differences in peritoneal permeability. To determine if early estimation of peritoneal permeability can predict the prognosis of CAPD, we used data from a personal dialysis capacity (PDC) study group in Japan to investigate patient and technique survival rates. Based on the data from a previously reported, prospective multicenter study encompassing eight dialysis centers in Japan (Am J Kidney Dis 2002; 40:1045-54), we recalculated patient and technique survival data. We reviewed the records of 139 patients newly initiated on CAPD from January 1995 to December 1999. Peritoneal permeability was estimated by PDC test within the first year after initiation. We divided the patients into paired groups according to several peritoneal permeability variables as calculated by the PDC test (area, plasma loss, and peritoneal creatinine clearance), and we compared patient and technique survival rate between the groups. The mean age of the patients was 49.6 years +/- 14.9 years (standard deviation). The mean pore area of peritoneum was 19,936 +/- 8383 cm/1.73 m2. Estimation of patient survival by the Kaplan-Meier method showed 94.2%, 88.4%, 84.1%, and 79.7% at 1, 2, 3, and 5 years respectively. Estimated technique survival (including death as an endpoint) by the Kaplan-Meier method showed 90.6%, 76.8%, 67.4%, and 54.3% at 1, 2, 3, and 5 years respectively. In the high peritoneal permeability group (high area and high plasma loss), the technique survival at 5 years was significantly lower than in the low peritoneal permeability group [area: 55.9% (high) vs. 72.7% (low), p = 0.0459; plasma loss: 43.3% (high) vs. 62.8% (low), p = 0.0197). We observed no significant difference in patient survival between the high and low peritoneal permeability patients. In the high peritoneal creatinine clearance group, patient and technique survival were both significantly lower than in the high peritoneal creatinine clearance group. Patients with high peritoneal permeability as calculated by the PDC test at the start of PD had a poor prognosis for technique and patient survival on CAPD. We conclude that early estimation of high peritoneal permeability can predict poor outcome for patients on CAPD.

Creatinine↗
PubMed2006

The newly developed calcium antagonist, azelnidipine, increases drain volume in continuous ambulatory peritoneal dialysis patients.

Many patients undergoing continuous ambulatory peritoneal dialysis (CAPD) receive antihypertensive agents, including calcium antagonists, which produce reflex tachycardia through activation of the sympathetic nervous system. Azelnidipine, a newly developed calcium antagonist, has unique characteristics in that it causes less reflex stimulation of the sympathetic nervous system. In the present study, we used a crossover method to compare the effects of amlodipine (5-10 mg daily) and azelnidipine (8-16 mg daily) on drain volume and weekly creatinine clearance in 9 CAPD patients (3 women, 6 men; mean age: 64 +/- 5 years; mean duration of CAPD: 1.8 +/- 0.6 years). Each calcium antagonist was administered for 3 months and then switched for the other. As compared with amlodipine, azelnidipine increased drain volume by 13% +/- 2% (p < 0.05) and weekly creatinine clearance by 12% +/- 2% (p < 0.05). At the same time, we observed no significant differences in blood pressure and urine volume. The increases in drain volume produced by azelnidipine resulted from less activation of the sympathetic nervous system. We therefore suggest that activation of the sympathetic nervous system induced by calcium antagonists may be important in the regulation of drain volume in CAPD patients.

Amlodipine↗
PubMed2006

Efficacy and safety of meropenem plus tobramycin followed by meropenem plus vancomycin for treating peritonitis in patients on continuous ambulatory peritoneal dialysis.

Peritonitis is a serious complication in patients on peritoneal dialysis. We examined the efficacy of MTV therapy [first 7 days: meropenem 0.5 g intravenously (IV) twice daily, plus tobramycin 15 mg intraperitoneally (IP) in every dialysis bag; next 7 days: meropenem 0.5 g IV twice daily, plus vancomycin 8 mg/kg IP in every bag after a 1-g loading dose] on peritonitis in patients undergoing continuous ambulatory peritoneal dialysis (CAPD), comparing it with the treatment previously recommended by the International Society for Peritoneal Dialysis (combination of first-generation cephalosporins and aminoglycosides). We treated 36 CAPD peritonitis episodes with MTV therapy. Outcome measures were primary response rate at day 14 and relapse rate within 28 days after the start of antibiotic therapy. The primary response rate was 34/36 (94.4%). No patients treated with MTV therapy required catheter removal. We observed no serious side effects in these patients. We conclude that MTV therapy may be an even better choice of treatment for peritonitis in patients on CAPD than was the previous empirical treatment (combination of first-generation cephalosporin and aminoglycosides).

Anti-Bacterial Agents↗
PubMed2006

Long-term follow-up of patients treated with a combination of continuous ambulatory peritoneal dialysis and hemodialysis.

Continuous ambulatory peritoneal dialysis (CAPD) and hemodialysis (HD) both have advantages in the treatment of patients with renal failure. In CAPD, solute removal is sometimes insufficient in patients who have a relatively large muscle mass that produces high levels of creatinine. To compensate for this deficiency, frequent exchanges and large dialysate volumes are required. We previously reported that once-weekly HD helps CAPD patients who experience insufficient solute removal. In the present study, we followed, for more than 3 years, 9 CAPD patients who underwent additional weekly HD. Add-on HD therapy significantly increased the subjects' weekly peritoneal creatinine clearance to 45 +/- 3 L (mean +/- standard deviation); these values rose to more than 60 L over the course of the study. Our findings suggest that the combined use of CAPD and HD improves solute clearance in CAPD patients who are insufficiently dialyzed.

Creatinine↗
PubMed2006

Continuous ambulatory peritoneal dialysis is effective for patients with severe congestive heart failure.

Although the use of continuous ambulatory peritoneal dialysis (CAPD) to treat refractory heart failure is not new, in combination with current medical treatment it improves patients'symptoms as well as their cardiac function. We started 16 patients (13 men with a mean age of 66.3 +/- 2.8 years, and 3 women with a mean age of 72 +/- 4.2 years) on CAPD. All patients were symptomatic with congestive heart failure. Mean left ventricular ejection fraction (LVEF) before the start of CAPD was 31% +/- 3%. Introduction to CAPD was associated with a significant improvement in LVEF (to 44% +/- 6%, p < 0.05) and in blood pressure control at 1 year. Also at 1 year, 87% of patients were classified as New York Heart Association grade I or II (maximum possible grade is grade III). These results suggest that CAPD is a treatment of choice for patients suffering from a combination of congestive heart failure and chronic renal insufficiency.

Aged↗
PubMed2006

Risk factors for vascular complications in patients on peritoneal dialysis.

The major cause of death in patients on peritoneal dialysis (PD) is vascular complications, including congestive heart failure, cerebrovascular disease, and myocardial infarction. To clarify the risk factors for vascular complications in patients on PD, we investigated the clinical course of PD in patients with and without cardiovascular and cerebrovascular complications. From among 327 end-stage renal disease (ESRD) patients initiated onto PD from April 1995 to March 2005 in the Kidney and Dialysis Center, Saitama Medical School, 8 developed de novo cardiovascular and cerebrovascular complications (CVD group--mean age: 58.3 +/- 4.9 years; 5 men, 3 women). We compared data pertaining to body weight, blood pressure, blood chemistry, and cardiothoracic ratio (CTR) between the CVD group and an age- and sex-matched control group (n = 8; mean age: 57.5 +/- 4.0 years). At baseline, we observed no significant differences of body weight, blood pressure, CTR, hemoglobin, total cholesterol, triglycerides, HbA1c, or serum albumin between the CVD group and the control group. In the CVD group, 1 month before the onset of CVD, serum albumin was significantly lower than in the control group (2.9 +/- 0.2 g/dL vs. 3.8 +/- 0.1 g/dL, p = 0.0029). Body weight in the CVD group was significantly lower than in the control group (56.8 +/- 2.8 kg vs. 63.0 +/- 2.9 kg, p = 0.0086). No significant differences were observed in blood pressure, CTR, hemoglobin, total cholesterol, triglycerides, or HbA1c between the groups. A decrease in serum albumin after commencement of dialysis is an important risk factor for, and a strong predictor of vascular complications in patients on PD. To help prevent vascular complications, it is important to monitor and manage serum albumin in patients on PD.

Blood Chemical Analysis↗
PubMed2006

[Survey on the current status of delivered informed consent for renal replacement therapy among patients with end-stage renal disease].

We conducted a survey on the adequacy of delivered informed consent (IC) among patients with end-stage renal disease (ESRD) regarding the information provided on renal replacement therapies (RRT): Hemodialysis (HD), peritoneal dialysis (PD), and renal transplantation (RTx). A self-assessment style of questionnaire entitled "Informed consent for the selection of dialysis therapy modality" was prepared for evaluation, and the adequacy of IC was scored by 5 grades ranging from "excellent" to "bad". The questionnaire was sent to all the JSDT registered facilities (n=3484), and 480 centers replied (13.8%). Among these, 407 centers had patients introduced onto some form of RRT modality in the last 12 months. As to the adequacy of delivered IC for each modality, "excellent and good" status was reported as follows: 80.8% in HD, 49.8% in PD, and 32.5% in RTx, respectively. The major reason for "poor and bad" IC adequacy in PD and RTx, was "not available in the facility". By analyzing the facilities stratified by the clinical experiences of each modality in the past, poorly delivered IC for PD and RTx was revealed in centers lacking experience. Delivered information about RRT to ESRD patients may be biased in Japan. The findings of this study suggested that a lack of medical experience of the modality contributes to insufficient IC.

Disclosure↗
PubMed2005

Exogenous 5'-nucleotidase improves glomerular autoregulation in Thy-1 nephritic rats.

Experiments were performed to characterize renal hemodynamics in Thy-1 nephritic rats. A monoclonal antibody against Thy-1 was intravenously injected to induce mesangiolysis in rats, and 2 days later renal hemodynamic responses to variations in blood pressure were determined. In the first series of experiments, autoregulation of renal plasma flow (RPF) or glomerular filtration rate (GFR) was impaired in nephritic rats. In response to a reduction in blood pressure (98 +/- 2 to 80 +/- 1 mmHg), both RPF (4.17 +/- 0.63 to 3.20 +/- 0.45 ml x min(-1) x g kidney wt(-1), P < 0.05, n = 6) and GFR (0.88 +/- 0.05 to 0.75 +/- 0.06 ml x min(-1).g kidney wt(-1), P < 0.05) were decreased in nephritic rats. Intravenous administration of furosemide and 30% albumin, both of which inhibit tubuloglomerular feedback, diminished renal autoregulation in control but not nephritic rats. In the second studies, the infusion of 5'-nucleotidase, an enzyme expressed on mesangial cells, into a renal artery ameliorated the magnitude of autoregulatory decrements in GFR in nephritic rats (-16 +/- 5 to -6 +/- 2%, P < 0.05, n = 6), but this enzyme failed to alter renal autoregulation in control rats. In the third studies, the effects of indomethacin were examined in nephritic rats. Inhibition of prostaglandin synthesis reduced RPF (4.07 +/- 0.30 to 1.54 +/- 0.22 ml x min(-1) x g kidney wt(-1), P < 0.05, n = 5) and GFR (1.03 +/- 0.18 to 0.69 +/- 0.13 ml x min(-1) x g kidney wt(-1), P < 0.05) in nephritic rats. However, cyclooxygenase inhibition failed to restore renal autoregulation in nephritic rats. Our results indicate that renal autoregulation is impaired in Thy-1 nephritis. Furthermore, the present data provide evidence that prostanoids contribute to maintain renal circulation in nephritic rats. Finally, our findings suggest that mesangial cells and/or 5'-nucleotidase plays an important role in mediating renal autoregulation.

5'-Nucleotidase↗
PubMed2005

Role of platelet factor 4-heparin complex antibody (HIT antibody) in the pathogenesis of thrombotic episodes in patients on hemodialysis.

Heparin-induced thrombocytopenia (HIT) is a severe complication in patients on hemodialysis (HD). It has been reported that platelet factor-4 (PF-4)-heparin complex antibody (HIT antibody) plays an important role in the pathogenesis of this serious complication. In the present study, we investigated the role of HIT antibody in the pathogenesis of thrombotic complications including shunt failure, cerebrovascular disease (CVD) and atherosclerosis in patients on dialysis. Plasma concentration of HIT antibody in patients on HD was 0.143+/-0.008 (n=105). This was significantly higher in patients on continuous ambulatory peritoneal dialysis (CAPD: 0.087+/-0.006, p=0.0008, n=22) and in non-dialysis patients (0.113+/-0.011, p=0.0011, n=12). There was a significant negative correlation between HIT antibody and the duration of dialysis. However, no significant correlation was found between HIT antibody and other factors including age, dose of heparin, platelet count and hemoglobin. There was a significant correlation between the number of failed arteriovenous fistula and HIT antibody levels. In addition, in patients with a history of CVD, plasma concentrations of HIT antibody were significantly higher compared with patients without CVD (CVD(+): 0.200+/-0.029 vs. (-): 0.127+/-0.005, p<0.0001). It is possible that genetic factors may also play a role in the expression of HIT antibody. From these data, it appears possible that HIT antibody plays an important role in the pathogenesis of thrombosis in patients on HD. Further studies are needed to clarify the role of HIT antibody in the pathogenesis of thrombotic episodes in these patients.

Adult↗
PubMed2005

Encapsulating peritoneal sclerosis--a clinician's approach to diagnosis and medical treatment.

Encapsulating peritoneal sclerosis (EPS) is recognized as a serious complication of continuous peritoneal dialysis. A preliminary diagnosis of EPSis usually based on clinical signs and symptoms, which commonly include abdominal pain, nausea, vomiting, anorexia, abdominal fullness, an abdominal mass, bowel obstruction, and radiologic findings, including abdominal roentgenogram, contrast studies, ultrasound studies, and computed tomography. The diagnosis is confirmed by laparoscopy or laparotomy showing the characteristic gross thickening of the peritoneum enclosing some or all of the small intestine in a cocoon of opaque tissue. A variety of therapeutic approaches to EPS have been reported. This review discusses medical treatment of EPS and includes an overview of the clinical features and diagnostic aspects of the condition.

Humans↗
PubMed2005

Recommendations on the management of encapsulating peritoneal sclerosis in Japan, 2005: diagnosis, predictive markers, treatment, and preventive measures.

This comprehensive update on the management of encapsulating peritoneal sclerosis incorporates insights gained from recently published findings and the accumulated experience of the authors. Aspects covered include diagnosis, risk factors and predictive markers, treatment, and prevention, including criteria for withdrawal from peritoneal dialysis.

Biomarkers↗
PubMed2005

Successful use of icodextrin in elderly patients on continuous ambulatory peritoneal dialysis.

In peritoneal dialysis (PD), a 7.5% polyglucose-containing dialysis solution (icodextrin) provides prolonged ultrafiltration as compared with glucose-based dialysis solutions. In the present study, we attempted to clarify the safety and effectiveness of icodextrin in elderly patients on continuous ambulatory peritoneal dialysis (CAPD). Clinical data and outcomes of 16 patients aged 65 or older were monitored for 12 weeks before and during icodextrin treatment. The group included 13 men and 3 women with a mean age of 69 +/- 5 years (range: 66-78 years). The underlying kidney disease was chronic nephritis in 7 patients, diabetes mellitus in 8 patients, and nephrosclerosis in I patient. From the beginning of peritoneal dialysis, 1 patients had been treated with icodextrin; the other 10 were changed to icodextrin from glucose dialysis solution. At the end of study, body weight had increased to 63.8 +/- 9.3 kg from 61.6 +/- 9.3 kg, accompanied by an increase in ultrafiltration to 480 +/- 207 mL daily from 369 +/- 436 mL daily. No significant change in urine volume occurred. Despite the increase in body weight, cardiothoracic rate decreased to 51.1% +/- 3.4% from 52.3% +/- 4.9%. All patients reported an improvement of edema and appetite. Edema scores were significantly decreased to 0.85 +/- 0.90 from 1.63 +/- 0.96 (p < 0.03). No adverse side effects were associated with the use of icodextrin. From the foregoing data, we concluded that, as compared with conventional glucose solution, icodextrin has beneficial effects on ultrafiltration volume and clinical symptoms in elderly patients on CAPD.

Aged↗
PubMed2004

Effects of an angiotensin II receptor blocker, valsartan, on residual renal function in patients on CAPD.

BACKGROUND: Both residual renal function and blood pressure (BP) control contribute to patient survival in patients receiving continuous ambulatory peritoneal dialysis (CAPD). It is unknown whether antihypertensive drugs affect residual renal function in addition to BP reduction. METHODS: We examined the effects of an angiotensin II receptor blocker, valsartan, on residual renal function and total clearance (renal and peritoneal) in 34 Japanese CAPD patients from 3 months to 2 years after the start of dialysis therapy. Patients were randomly assigned to valsartan (n = 18; age, 63.5 +/- 3.7 years; 11 men, 7 women) or a control group (n = 16; age, 63.5 +/- 3.3 years; 10 men, 6 women). Conventional antihypertensive treatment was continued in all patients to achieve the target BP in both groups of 130/80 mm Hg or less, measured at home. RESULTS: BP reduction was similar in the valsartan and control groups. Valsartan significantly slowed the progressive decline in both residual renal function (3.2 +/- 0.3 to 4.3 +/- 0.7 mL/min/1.73 m2) and total clearance (42.1 +/- 3.2 to 48.3 +/- 4.8 L/wk/1.73 m2) by dialysis in CAPD patients compared with controls (5.9 +/- 0.5 to 2.8 +/- 0.4 mL/min/1.73 m2; 47.1 +/- 4.8 to 31.4 +/- 5.2 L/wk/1.73 m2). CONCLUSION: This study shows that in patients with hypertension starting CAPD therapy, valsartan slows the decline in residual renal function and contributes to maintenance of weekly creatinine clearance and Kt/V (fraction per dialysis), which are the major factors contributing to the mortality and morbidity of CAPD patients. This effect appears to be mostly a result of maintaining residual renal function.

Angiotensin II Type 1 Receptor Blockers↗
PubMed2004

Changes in the organisms of resistant peritonitis in patients on continuous ambulatory peritoneal dialysis.

Peritonitis is one of the most serious complications of continuous ambulatory peritoneal dialysis (CAPD). Approximately 20% of peritonitis infections have been reported to be resistant to initial therapy, either failing to resolve with appropriate antibiotics or relapsing within 2 weeks of antibiotic discontinuation. To investigate the current situation with regard to resistant peritonitis, we retrospectively examined the incidence and the organisms of resistant peritonitis in our unit over a period of 9 years. From January 1, 1994, to January 1, 2003, we introduced 325 patients onto CAPD. At January 1, 2003, we followed up 172 patients who were receiving CAPD in our unit. During 1994-1996, 12 cases of peritonitis and 3 cases of resistant peritonitis (25%) occurred among our patients. Microbiologic examination revealed that the organisms involved in peritonitis were alpha-streptococcus (17%), coagulase-negative staphylococcus [CNS (17%)], and methicillin-sensitive Staphylococcus aureus [MSSA (17%)]. The organisms of resistant peritonitis were methicillin-resistant S. aureus [MRSA (67%)] and methicillin-resistant CNS (33%). During 1997-1999, 39 cases of peritonitis and 13 cases of resistant peritonitis (33%) occurred among our patients. The most frequently cultured organisms in peritonitis were CNS (26%), Candida species (13%), and alpha-streptococcus (10%). The organisms of resistant peritonitis were methicillin-resistant CNS (46%) and Candida species (38%). In the most recent 3-year period (2000-2002), our patients experienced 57 cases of peritonitis and 24 cases of resistant peritonitis (42%). The organisms of peritonitis were alpha-streptococcus (46%), CNS, MSSA, Escherichia coli, and Candida species (38%). However, the organisms of resistant peritonitis were methicillin-resistant CNS (13%), Candida species (21%), Pseudomonas aeruginosa (13%), Serratia (13%), Citrobacter (13%), and Corynebacterium (13%). In the last several years, methicillin-resistant CNS has come to be main organism of resistant peritonitis. In addition, opportunistic infection has become a serious peritonitis problem. Given these data, we conclude that the incidence of resistant peritonitis is increasing and that the organisms of resistant peritonitis are changing.

Bacterial Infections↗
PubMed2004

Blood pressure monitoring by cellular telephone in patients on continuous ambulatory peritoneal dialysis.

We have developed a new telemedicine system that uses a cellular telephone and Internet Web site to monitor changes of blood pressure (BP) in patients on continuous ambulatory peritoneal dialysis (CAPD). An I-converter data collection system directly transmits all data on BP and heart rate (HR) measured by a fully automatic device (HEM-705IT: Omron Life Science, Tokyo, Japan) to a cellular telephone. The cellular telephone then sends the data directly to the main server at the NTT DoCoMo data center. All data, including BP and HR from each patient, are accumulated in the server. Application service provider technology (ASP) connects that system directly to the Internet. Any time and anywhere, each patient can use a cellular telephone or the Internet Web site to monitor, in graph form, changes in their data. The average data at each collection point are calculated and shown on the Web site. All data collected by cellular telephone are also calculated and sent directly, in real time, to the physician's office. Currently, we are using this telemedicine system for 44 hypertensive patients on CAPD at our center. In the present study, we used the telemedicine system to evaluate changes in 24-hour BP. We followed 20 CAPD patients, monitoring changes in BP for 3 months. At the end of study, we found that the average daytime home BP was 137 +/- 8 mmHg over 80 +/- 4 mmHg and that the average nighttime BP was 128 +/- 7 mmHg over 72 +/- 4 mmHg. The overall average home BP was 132 +/- 7 mmHg over 76 +/- 3 mmHg. The average outpatient clinic BP was 155 +/- 9 mmHg over 86 +/- 5 mmHg. The measured systolic and diastolic BP at the out-patient clinic were significantly higher than those measured at home. As measured at the outpatient clinic, BP indicated that 7 CAPD patients (35%) were hypertensive (> 160/95 mmHg). However, as measured at home, BP indicated that only 4 CAPD patients (20%) were truly hypertensive (> 135/85 mmHg). We were therefore able to determine that 43% of our hypertensive patients had "white coat" hypertension. Our new telemedicine system that monitors BP by cellular telephone provides great advantages in monitoring BP at home in patients on CAPD.

Adult↗